Enhanced quality and optimized volatile profile of Jerusalem artichoke chips: A combined approach of pretreatment optimization and hybrid vacuum freeze-hot air drying

This study investigated the effects of a combined pretreatment strategy and hybrid drying method on the quality attributes and volatile compound profile of Jerusalem artichoke chips, a promising non-food energy crop. Three pretreatment parameters were optimized using response surface methodology, including blanching time (30-90 s), NaCl concentration (0.4-1.2%), and maltodextrin concentration (4-12%). These optimizations improved color, rehydration capacity, hardness, microstructure, and volatile compounds. The optimal conditions were 67 s blanching time, 0.97% NaCl, and 8.35% maltodextrin. Under these conditions, L * values increased significantly from 66 ± 1 to 79.8 ± 0.9, rehydration ratio improved from 3.0 ± 0.1 to 3.9 ± 0.1, and hardness reached 1,240 ± 60 g. GC-MS-based metabolomic analysis identified 256 different volatile metabolites in the samples. Results showed that with our optimized pretreatment and hybrid drying method, desirable fruity volatiles increased approximately 4.4-fold while undesirable nitrogen-containing off-flavors decreased by approximately 90-fold compared to conventional processing. The hybrid method significantly improved overall chip quality by effectively preserving key aroma compounds essential for sensory acceptance. The results offer practical insights for developing Jerusalem artichoke chips with enhanced quality and better flavor profiles. This supports wider adoption of this non-food crop in the snack food industry. • Optimal pretreatment: 67 s blanching, 0.97% NaCl, 8.35% maltodextrin • Enhanced color, texture, rehydration, and microstructure • Retained fruity and green notes, suppressed off-flavors via modulation